title: Characterization of free-standing PEDOT:PSS/iron oxide nanoparticle composite thin films and application as conformable humidity sensors.
abstract: In this study, a new simple, fast, and inexpensive technique for the preparation of free-standing nanocomposite ultrathin films based on the conductive polymer poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) and embedding iron oxide nanoparticles (NPs) is presented. These nanofilms were fabricated by a single step of spin-coated assisted deposition in conjunction with a release technique ("supporting layer technique") to detach them from the substrate. Free-standing nanofilms can be easily transferred onto several substrates due to their high conformability, preserving their functionalities. The effect of the addition of iron oxide nanoparticles on the structural and functional properties of the PEDOT:PSS nanofilms is investigated through topography, thickness, magnetic, magneto-optical activity, and conductivity characterizations. PEDOT:PSS and PEDOT:PSS/iron oxide NP nanofilms were tested as resistive humidity sensors. Their sensitivity to humidity was found to increase with increasing nanoparticle concentration. On the basis of these results, it is expected that these composites may furnish inexpensive and reliable means for relative humidity detection.
authors.affiliation: Center for Micro-BioRobotics @SSSA, Istituto Italiano di Tecnologia, Pontedera, 56025 Italy. silvia.taccola@iit.it
authors.forename: Silvia
authors.initials: S
authors.lastname: Taccola
authors.forename: Francesco
authors.initials: F
authors.lastname: Greco
authors.forename: Alessandra
authors.initials: A
authors.lastname: Zucca
authors.forename: Claudia
authors.initials: C
authors.lastname: Innocenti
authors.forename: César de Julián
authors.initials: Cde J
authors.lastname: Fernández
authors.forename: Giulio
authors.initials: G
authors.lastname: Campo
authors.forename: Claudio
authors.initials: C
authors.lastname: Sangregorio
authors.forename: Barbara
authors.initials: B
authors.lastname: Mazzolai
authors.forename: Virgilio
authors.initials: V
authors.lastname: Mattoli
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000737:chemistry*; D005290:Ferric Compounds / Q000737:chemistry; D006813:Humidity; D053761:Nanocomposites / Q000737:chemistry*; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry*; D014867:Water / Q000032:analysis*
chemical_list: D019086:Bridged Bicyclo Compounds, Heterocyclic; D005290:Ferric Compounds; D011108:Polymers; D011137:Polystyrenes; C121383:poly(3,4-ethylene dioxythiophene); D014867:Water; C000499:ferric oxide; C003321:polystyrene sulfonic acid